Problem:

The disabled snap packages are using space in your hard disk.

Solution:

To solve it, You can list and delete them!.

Step by step:

  1. Open a Terminal and list all the snap packages:

     snap list --all

    You can filter to get the disabled only:

     snap list --all | grep "disabled"

  2. Remove a specific revision (“version”) snap package.

     $ sudo snap remove <snapname> --revision=<revision_number>

    Example:

         sudo snap remove okular --revision=172

  3. Finally, you can verify that the package was successfully removed.

     snap list --all

Optionally

You can use this script for deleting ALL the disabled snap apps:

LANG=C snap list --all | awk '/disabled/{print $1, $3}' |
    while read snapname revision; do
        sudo snap remove "$snapname" --revision="$revision"
    done
echo "Deleting cache"
sudo sh -c 'rm /var/lib/snapd/cache/*'

Source: